The Rock: Defeat The Rock with Stone Cold on the Legend difficulty setting ($210,000).

Triple H DX Entrance: Buy the DX attire ($30,000).

Vince McMahon: Defend a championship in 24/7 mode ($110,000).

Vince McMahon (Bald): Buy the original Vince McMahon ($60,000).

WCW Classic Championship: Become be a Hall of Famer ($20,000).

WWF Attitude Era Championship: Become be a Hall of Famer ($20,000).

Arenas

Get the indicated number of Hall Of Fame mode points to unlock the corresponding arena:

December to Dismember: 8

ECW One Night Stand: 7

Great American Bash: 10

New Year's Revolution: 9

No Way Out: 5

Summerslam: 11

Vengeance: 6

Wrestlemania 23: 12

Easy wins

When playing against someone in 24/7 mode, play as the person you
want to defeat. When the match begins, get a weapon and hit the referee
if you do not want to injure your player. You will win by DQ. Note: This does not work for a match with DQ off.

Set bat on fire

In an ECW Extreme Rules match, once you get your finisher, you can
get a baseball bat covered with barbed wire. You can use your finisher
to set the bat on fire.

Quicker finisher

Use your taunt to get your finisher faster. This will not work for
wrestlers such as The Undertaker, but it will work for wrestlers like
Rey Mysterio.